#help-27
1 messages · Page 209 of 1
okay i'm doing it tediously (digitally) then
wow it's a really nice solution
||8cos^4(x)||
Well idk what i did
what did you do
let's focus on one formula
since we're dealing with cosines
let's deal with cosines
cos(2x) = 2cos^2(x) - 1
well for cos(4x) just sub every x for 2x
cos(4x) is therefore 2cos^2(2x) - 1
Just second
How is this possible
Okay
let's stop confusing ourselves with x and 2x
cos2y = cosycosy - sinysiny
let y = 2x in this case
Okay
it's the same thing
I technically did that
that's a good first step
Okay how do i continue ? Do i just use formulas more or?
express everything in cos(2x) and simplify would be my next move
Have you meant thay
Expansion...wait just second
Ok sorry, does this look better
expressing everything in terms of cos(2x) is simpler but you're on the right track
but your method will be more tedious
So i guess...cos^2 (2x)= cos^4(x)-sin^4(x)
... right?
it still works
I don't know...how to. I am so dumb
but now your powers are different
So i can continue like that?
I just realised that
Okay thanks
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How can I find the oblique asymptotes of this function?
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1. I don't know where to begin.
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what exactly do you mean by oblique asymptote? A straight line?
In the question it tells me that there are multiple oblique asymptotes, my task is to find them
i have no more information then the function
and an oblique asymptote is like an asymptote that has a cartesian description
for example x = y
i would not expect that function to have an oblique asymptote
could you post a picture of the original problem statement?
okay just a second
only vertical asymptotes
yeah the drawing is messed up
there are formulas for the oblique asymptotes, are you familiar with them?
yes
this is the most likely mistake
so to determine whether there are any or not you can apply them
starting with a?
yes
this is the correct curve
hmm ok
well i would still like to attempt because i wont have access to geogebra during my exam
if e.g. limit doesn't turn out finite then an oblique asymptote won't exist
by finite you mean a tangible expression, like for example y = x?
so if i follow (sqrt(x^4-16)/2)/x I shouldnt get anything tangible?
okay
because it seems like this should also have an oblique asymptote
but this is actually doable in memory
but take your time and try to solve it then tell me your result
Show your work if possible.
okay i'll try and write it down nice, should pop up in a few mins
I'm asking because it doesn't seem to be right
"infinity/infinity" is an indeterminate form, so you can't just say it evaluates to 1 out of hand
consider that x^2/x = x for all x ≠ 0
well then i would have x*sqrt(1-16/x^4)
and I dont exactly know what to do with that
take the limit as x approaches infinity
so what can we say about our oblique asymptote if the limit implies it has infinite slope?
that its a vertical asymptote?
i dont really know
because infinity times a always equels infinity
well we assumed that there must be a diagonal line that the function approaches, but the slope of such a line is not defined, so can such a line exist?
no
so the function does not have an oblique asymptote
then what kind of asymptotes would it have then?
i cant see a horizontal one
nor any vertical ones
although i suppose the whole area of ]-2,2[ is kind of an asymptote
i would conclude that it has none
okay
thank you for your help, and everyone else beforehand. I appreciate it a lot!
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How to do the last step?
My guess is that they’re using the thin svd somehow but I’m not too sure how they got the matrix
What's $\Sigma_{r}$ in that context?
cjg#1618
It is the square diagonal matrix containing all singular values in \Sigma
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How do i do 6? I just want a starting guide not the full answer but i dont know where to start
Do you know what the inverse of log is?
no
ln is a log
the base of just log depends on convention. i just assumed it to be e
Most likely base 10
Base 10 log
Then what would be the inverse?
10^7x+1??
Well you would have 10^(log(…))
I'm confused
If you have log(x) then you can apply base 10 so you have 10^log(x). Then the base 10 cancels the log
You can undo the logarithmic functions by setting both as the power of base 10
but you need to change the 1 to log of something (well, you don't need to I guess)
This??
no, 10 to the power of the entire RHS
you still need the logs there, too
[ \log (\dots) = \dots ]
Apply base 10
[ 10^{\log (\dots)} = 10^{\dots} ]
shsgd
Then the 10 cancels the log, which leaves just the dots
I need to see the dots as x gimmie a sec
[ \log (x) = x ]
Apply base 10
[ 10^{\log (x)} = 10^{x} ]
Sprout
Yeah but what about the leftover 1?
you are applying base 10 to the entire equation so you have 10^{log(x) + 1}
what power law can you apply to deal with the 1?
Recall ( x^{a+b} = x^a \cdot x^b )
shsgd
This? Ignore bottom 10
well remember you are applying base 10 to the entire equation, so you include the logs
,, 10^{\log (7x+1)} = 10^{\log (x-2) +1}
shsgd
,, a^{\log_a (x)} = x
shsgd
use this ^
second last line can be crossed out
and remember what you have to do with the + 1 before cancelling the logs
Make it a 10?
👍
it's still not right
after using the exponent law on the + 1 what do you have?
10
I mean what do you get for the entire equation
not + 10, remember this is the rule
I redid it
Yeah that's definitely one way to do it
So i see what i went wrong
The two should have been a 20
And the x should be 10x
Actually nvm
But idk
,, 10^{\log (x-2) + 1} = 10^1 \cdot 10^{\log (x-2)}
shsgd
then cancel the log and you have
10(x-2)
I suggest you try more problems that use power laws. Getting comfortable with them will really boost your algebra skills
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So lim h->0 f(x+h)-f(x)/h means there’s a small arbitrary change at h but why do we say h->0 ? Like what about if we say the change is about h=0.5 !!
I know it’s a small arbitrary value near to 0 because it have to be a linear line
But why do we say 0?
why do we evaluate h at 0
We are exactly concerned with changes that are "as small as possible"
Note we don't evaluate at h = 0. We take the limit as h approaches 0. So "a very small h".
Oh so we approximate it ?
like from the biggest numbers
Approximate which, sorry?
the h
If we don’t evaluate it at h=0 then why do we take this limit ?
And how is it still possible to give us the difference ? The secant line would start at 0 if we take the limit (evaluate) it at h=0
we cant evaluate at 0
Oh
yes because it’s improper function
It will diverge
You might be trying to equate "evaluate at 0" and "take the limit to 0". They are not the same thing.
Specifically, evaluation fails. You can't plug in h = 0 without a division by 0.
But the limit can succeed.
What’s the correct definition of Take the limit then
There's a specific definition called the "Epsilon-delta definition". If your class hasn't shown it to you, you likely don't want to see it
intuitively, as h gets closer snd closer to that value
ye i dont think elementary calc curriculum teaches epsilon delta
But you can think of the limit as "letting h get really small, and seeing where (f(x+h) - f(x)) / h goes"
Oh , alright so suppose we say h=0.5 and f(x) is defined at x=1 and then the rate of change is going to be x=1.5 and the secant line will start from x=0.5 and end at 1.5 right ?
If you plug in x = 1 and h = 0.5, you'll find the slope of the secant line between x = 1 and x = 1.5
You're basically using the slope formula
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Is this a wrong way to go about the problem or is this ok
e^(lna)=a
You can cancel out the ln by raising e
i think
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how do you get the second equation
i mean x value i
i understand that first is 42 degrees
but like
i thought you just add 90
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can somone explain what rafilou tried to say bc in can understand nothing
@restive river the secret has to do with the properties described after each of these definitions:
https://en.m.wikipedia.org/wiki/Bijection,_injection_and_surjection
In mathematics, injections, surjections, and bijections are classes of functions distinguished by the manner in which arguments (input expressions from the domain) and images (output expressions from the codomain) are related or mapped to each other.
A function maps elements from its domain to elements in its codomain. Given a function
...
hi melvin
i actually know the properties of these of kind of functions
my school didnt really tell me about the properties tho but i know the definitions
but let me go through it
I never understood these things, I was always a little off for at least one of these
rafilou plugged in x=f(y)
f(f(y)-f(y))=f(f(y))+f(y)^2+f(f(y))-1
rearranges into 2f(f(y))=-f(y)^2+f(0)+1
ok i get what you mean qwerty
but can you tell me how they got this
bc theyre correct, the ans is 2
is that some kind of propery melvin just talked about
if f is surjective then there exists some value c such that f(c)=0
then we plug in y=c and get
2f(f(c))=f(c)^2+f(0)+1
since f(c)=0 this gives 2f(0)=f(0)+1 which means f(0)=1
now plugging f(0)=1 into 2f(f(y))=-f(y)^2+f(0)+1 we get 2f(f(y))=-f(y)^2+2
Furthermore due to surjectivity for any x there exists y such that f(y)=x and plugging x=f(y) gives you the desired result
explain this a bit more pls
im clear till this step
Since f is surjective, for every u in R there exists a v such that f(v)=u
true
plugging in y=v we get
2f(f(v))=-f(v)^2+2
but we have f(v)=u
so 2f(u)=-u^2+2
since u is arbitrary, f(u)=(-u^2+2)/2 must hold for all real number u
which means that the function must be f(x)=-x^2/2+1
@restive river is this clearer?
hold on lemme process a bit
@near jolt im able to understand everything
i have a one more question
from this question itself
the only 'if' we are using here is that f should be surjective, and if its surjective this is true
yeah, we have not proved that it is surjective (i dont even know if it is necessarily surjective)
or are there other thing too apart from f(c)=0?
man but what if my teacher asks how i know its a surjective or not
out answer is totally based on an assumption
im aware
there is probably a better method (or a way to prove it is surjective)
ill dm u if i think of something ig
ill also ask my teacher about this question, im curious to see what's the other method
ok i have class today, ill tell you if my teacher tells me some other method
alr can i close the channel now?
yes
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f(x) is a polynomial with non negative real coefficients, if f(6)=24 and f(24)=1536, what is the maximum value of f(12)?
this might(?) be coorelated with cauchy-swarzh inequality since its the topic, but it can sometimes stray way from it
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hi guys any idea ofr ii)
which one?
these are vectors right?
you can sum up everything
n-1 to 1 - k-1 to 1
wait
are these vectors?
these are binomial coefficients
i don't think so
yeah
otherwise it won't make any sense
let me think wait a min
teah
they are
its all binomial stuff this worksheet
I think I got it
um
nCr + nCr-1 = n+1 C r
can you check this property pls if it is correct?
yeah
change k-1Ck-1 to kCk
oh
kCk-1 + kCk = k+1Ck
similarly keep adding
you will reach
n-1Ck-1 + n-1Ck = nCk
I think it solves the problem
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can some1 explain this to me? im a little confused since i guess why does this imply that the non-diagonal entries are 0
i guess i was thinking like if A = 3x3 with nondiagonal entries nonzero and the diagonal entries are B1 B2 B3, i dont see why the hypothesis holding implies A diagonalizable
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Let A and B be intersection points on the line y=2x+1 and the circle (x+1)^2 + (y-2)^2 = 5. The abscissa of point A is less than the abscissa of point B. Find a point C on the circle such that angle ABC is a right angle
$y = 2x+1 \ (x+1)^2 + (y-2)^2 = 5$
nashira._.
nashira._.
$x = 1, y = 3 \ \ x = -\frac{3}{5}, y = -\frac{1}{5}$
nashira._.
so since the x value of A will be less than B it means the top one is point B and the bottom one point A
so
$A \ (-\frac 35, -\frac 15) \ \ B (1,3)$
nashira._.
so now point C lies on the circle in such a way that angle ABC is a right angle
so I guess
$B \perp A$
nashira._.
so I guess
$y_A = m_Ax_A+c_A \ y_B = m_Bx_B+c_B$
since they are perpendicular
$m_A \times m_B = -1$
yeah im kinda stuck here
I mean I know I could probably substitute into m_A or m_B but that is yielding no results
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@crude solstice Has your question been resolved?
Won't you get a relation here ?
you could use this relation to construct the line perpendicular to AB that passes through B (you know the slope and a point it passes though) and plug that line into the circle to find C
but that's not the best way; recall properties involving circles and right angles
i know that if there is a right angle it means that the side opposite to the right angle should be the circumference
the diameter
oh yeah the diameter lmao
So I'd guess C has to be connected with A in such a way that angle B is 90 degrees now that way I have no idea
the diameter would be
$d = 2r = 2\sqrt 5$
nashira._.
@crude solstice Has your question been resolved?
in this case we know that the values of A and B are:
$A \ (-\frac 35, -\frac 15) \ \ B (1,3)$
nashira._.
so since we know A and B how would I solve for C?
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if I do a one-dimensional discrete cosine transform on a line of 8 values and I do two dcts separately for the even and odd values, how do I put the transformed values together?
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So i was messing around with a specific problem i saw that asked you to count how many times you write down the number 1 between 0 and some other number, which for this question was 99,999. I managed to come up with a formula that roughly gives how many times you'd have to write the digit one (or any digit for that matter) before you get to that value, but it's not very accurate except for around the powers of 10. I wanted to ask two questions: is there a way I can use this to also get a rough value for how many numbers have the digit one in them (as in, 111, does not count as 3 repetitions), and is there a more accurate way to do this?
$round(log(x) 10^{log(x)-1})$
Serphic
can you give some more examples
can't tell what you're asking for
nvm i think i understand now
you can probably do this combinatorially
taking 99999 for example, we can consider 5 length strings of elements from {0,1,...,9} (leading zeros allowed)
it would be messier for other numbers tho. 99999 is nice
but anyway there are 10^5 of these, and 9^5 that have no 1s. so the answer would be 10^5 - 9^5 (maybe off by 1 or 2 depending on if 0 and 99999 are included in the count or not)
i may be a little stupid, but would there not be 10^5 different elements rather than 5^10
oh oops
Also i dont think it works?
I managed to get recursive formula
ohh i see now
no i am the stupid one
yeah i have a recursive formula but its.. really weird
its like an infinite product or something
^ this one here is good
In numbers from 0 to 10^n - 1, there are 10^n - 9^n numbers with a 1 in them
w h a t
okay hold on
lemme process that
There are 10^n numbers between 0 and 10^n - 1
now how many of them don't have 1s?
note that those are exactly the numbers formed using those digits: {0, 2, 3, 4, 5, 6, 7, 8, 9}
Did you get it?
it feels a little too simple to be the solution but yeah i get it
wait so according to this formula, as the number of digits increase, most numbers start to have at least one of every digit in them, right?
Hmm why according to this formula?
I dont get the connection
limit as x goes to infty of (10^x - 9^x)/10^x = 1
ah
well yeah
thats quite obvious fact
the more digits there are, the higher is the probability that there is at least one of every digit
if you pick a random 1000 digit number it's probably going to have every digit
no but it is cool to have a (probably not extremely accurate) estimate of that probability
This counts just ones btw
not necessarily just ones tho
we could do 2 for this and it should be the exact same formula, no?
Yeah
all digits except for 0 have the same formula
but you cant get the estimate of probability that there is at least one of every digit just with this formula
valid
it does say that there are only 4 ones between 1 and 30 💀
Incorrect application
this formula only works for powers of 10
one last question, and im not sure if this is even valid
could i apply this in other bases by changing the base of the exponent and base of the log
so like
one sec
im just using log so that its numbers rather than powers of the base
would this hold true for like.. base 5 or something
yknow what actually nvm i think i have my answer lmfao
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if theres an infinite amount of real numbers between any 2 real numbers, how does time pass? how would 1 second become 2?
wouldnt an infinite amount of time need to pass for that to happen?
im not very knowledgeable on this so pardon me if my question is absurd
evidently not
how about theoretically?
each instant has 0 length, so you've got infinitely many instants of length 0
It could be that this indefinite instance of "0 * inf" happens to be the length of the interval
Ohhh youre rightt, because every instant is a part of the other
why are you mixing time with numbers?
because we measure time with numbers ig
you can't say that, time can be quantized, we simply don't know yet
number of seconds, minutes, hours
please don't mix physics with mathematics
interesting
why do we assume it is tho?
the invention of the clock is based on that idea no?
also i would say don't mix physical quantities with mathematics, even length can be quantized (planck's length), we simply don't know
you mean cant be?
are there any examples of a physical measurement that can be quantized?
at all?
that we know of
that doesn't prevent physicists and basically everyone else from considerings things that move as a function of time, and have a defined position at every real number
charge
and even if so, that doesn't prevent us from thinking about the possibility of a real-indexed time
I mean you don't take charges based on the charge of quarks, do you?
this makes complete sense tho
when you have many, you can assume it continuous, but at small scales, they are not
intuitively at least
they are quantized
exactly, it's just a real number
99.99% of the time, we are totally free to ignore quantization
it depends, if you are a particle physicist, 0.01% of time you are free to ignore quantization
if you are just an engineer 99.99% of the time, you are totally free to ignore quantization
and particle physicists are that 0.01% of the people on earth
anywho, thanks a lot guys
I appreciate it
ill close this now
feel free to take it to #discussion
.close
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How do I do part a
For independent events \( A \) and \( B \), the probability of their intersection is given by:
\[ P(A \cap B) = P(A) \times P(B) \]
tobi
@opaque talon Has your question been resolved?
but I did 0.1= (0.1p)(0.4) and i got it wrong
oh fucking hell
I said 0.1 times 0.4 was 0.4 in my maths exam
😭
thanks
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Yo can I get help with this
first of all you can factor out the 5
second of all you can bring the expression to a common denominator
then just use L'H
Ah k thanks
how do you get l'h?
L hospital
yeah how
by bringing it to a common denominator
I'm not sure the conditions are satisfied
ignoring the 5 you should get:
(1 - sqrt(1+t)) / (t sqrt(1+t))
which is a 0/0 limit
I think he saying find the derivative
only one item tend to 0
the top would be 1?
1 - 1 = ?
Do u mutiple the 5 to both numerator and denominator
just take it out of the limit
Ah I see bc the limit of itself it just itself
thr limit of 5 is 5 yes
I got it’s -5/2
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can someone breakdown the first step
-1 +1?
adding 0 presumably to get everything into a more easily workable form
they probably split the fraction next
the limit to 0 for (a^x-1)/x is ln(a)
so they just got it into a form where you can apply that
to get ln(25)-ln(16)
thats just basic properties of logs
if youre doing limits id presume you know the log laws at least
honestly dont
oh
barely passing calc, i have exam on wednesday
yeah iam super bad at math tho 🙁
aight thanks alot, that picture would also help a ton!
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Can someone explain how 2.667 and 7 make 29/3?
When I plugged it into the calculator I got a huge fraction
$2.\overline{6}$ (or 2.67 approximately) is $\frac{8}{3}$ as a fraction
Ari
$7 = \frac{21}{3}$
Ari
But
Yeah, because 2.67 is an approximation, not the actual decimal value
Desmos won't give you the exact value
The exact value is $2.6666...$
Ari
there are infinitely many
hence the ...
The idea is that its equivalent to 2 2/3, or 8/3
How do I get that
Since $1 = 0.999...$, $\frac{1}{3} = 0.333...$ and so $\frac{2}{3} = 0.666...$
Ari
Yeah but it’s not always a nice decimal
sure but in this case it is
you probably won't be asked to convert those into fractions then
One not-as-nice decimal you should know is $\frac{1}{7} = \overline{0.142857}$
Ari
I see
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two lines r parralel
prove that rectangle (abef) same as square (acd 0,0) no matter the value of b
@brisk urchin Has your question been resolved?
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!status
What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
1
!original
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
i assume you mean value of y? not value of b?
Nope
the question asked me to prove that the square always equalled to the triangle no matter the coordinates of B
equal area?
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@brisk urchin Has your question been resolved?
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hi this is a question with its answer, it asks to find if series converges or diverges
if they would have compared to 1/n^(3/2), then the limit would simplify to the limit of (ln(n))^2
which diverges
ln(n)/n^(3/2) is greater than 1/n^(3/2)
just because you know 1/n^(3/2) converges, this comparison is useless
all you know is that ln(n) / n^(3/2) is greater than a convergent series, that doesn't tell you whether or not it converges
but when you pick 1/n^a where a > 1 and a < 3/2 and you do the limit comparison test, you'll find that the limit goes to 0
they didn't have to use 1/n^(5/4)
but notice that if they used 1/n^a with a <= 1, it would diverge
so a > 1
and if a >= 3/2, then the limit would diverge
i see thanks
wait you mean converge right?
if a > 1 then it converges
1/n^a converges when a > 1, yes
i mean the limit used in the limit comparison
((ln(n))^2 / n^(3/2)) / (1/n^a)
= n^a * (ln(n))^2 / n^(3/2)
that diverges when a >= 3/2
which isn't useful for the comparison
since you want the limit to go to 0
got it
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Hello, good morning, please help me to understand this resolution, it asks to determine for which values n (natural) the limit is finite?
I don't understand the parts of the inequalities or what they were raised for by whoever did it
Hello, good evening, does sen(x) mean sin(x)
hmm ok
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Hello again, we want to solve a² + b² = c² in $Z^3$. $A$ is the ring $\mathbb{Z}[i]$, $a$ is odd and $b$ is even, (a +ib) and (a -ib) are comprime, a and b they're both elements of $\mathbb{Z}$ and there exists $\epsilon \in U(A)$ and $\beta \in A$ such that $a + ib = \epsilon \beta^2$; why can't $\epsilon$ be $-i$ or $i$?
abyssworld
so it changes the parity of a and b
i and -i
under the hypothesis that a is odd and b is even, you can't change their parity
and you meant to say that if epsilon is i or -i, a should be even and b odd? how so?
or
no, the opposite
if a is odd and b is even
you cannot have epsilon be -i or i
since the parity of a and b is fixed
ok, so if epsilon = i; we have a + ib = -x² -y² - 2iy if beta = x + iy; so
the imaginary part is still even here
if epsilon = i
yes
impossible
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Hi
what level is this?
wdym?
(sin (h/2) )²
how do i open this ?
that means
i mean sin h^2/4
right?
no
Wha
sin(h^2/4)
it means sin(h/2)*sin(h/2)
y0shi
how do i solve it further without making it sin^2 h/2 again?
half angle formulas
would you please elaborate ?
look
i know it will open to something like sin h/4
i mean sin h^2/4
$\sin(\frac{x}{2}) = \sqrt\frac{1-\cos(x)}{2}$
esca (@ with reply)
wait fuck yeah
sir no
whats the full problem
why did you say no to this?
im trying to make a formula, there's no quesiton sir
because sin^2(h/2) is not the same as sin(h^2/4)
elaborate ?
how old are you? wait
are you sure about this? im positive that u are wrong here
explain why
because then i can make it 0 if h= 0 and with that ican move aheadd
it is 0 when h = 0
i dont understand what youre trying to say
no
$\sin^2\left(\frac{h}{2}\right)=\left(\sin\left(\frac{h}{2}\right)\right)^2\ne\sin\left(\left(\frac{h}{2}\right)^2\right)$
kheerii
take notes
You’re squaring the whole function, not the input
That’s how trigonometric notation works
Please show the original problem, exactly as it was stated to you, with the entire original context. A picture or screenshot is best. If the original problem is not in English, then post it anyway! The additional context might still be helpful. Do your best to provide a translation.
are you trying to find
$\sin^2(\frac{h}{2}) = h^2$
?
esca (@ with reply)
$\left(\right)$ for brackets around fractions
kheerii
ah ty
i dont understand what youre asking then 
That’s not even true..
$\frac{\sin^2\left(\frac{h}{2}\right)}{h^2}=0$
esca (@ with reply)
doubt that’s a true identity
then i can cut it from the upper half somehow
its definitely not lol
this means sin^2 of everything is 0

@old carbon
Don’t ask random questions in text form
No
then is it possible?
EXACTLY
is the question asking for the limit as h approaches 0 of that?
that's why i did multiplied and then divided by 4
yeah kinda
why’re you plugging in 0 randomly
wdym kinda
That’s a completely different question
im guessing this is a language barrier
probably
chill guys, I know how to speak ingles, i just can't find the question right now
hold on
kheerii
okay what is q
@stable storm @feral agate @nova glen
is this the original problem?
i don't have the question, but i can assure you the above thing is 101% correct
i just don't know how we went from q/2 to q/8
the limit is 1/4
elaborate?
well this expression is 1/4. you can find it with l'hopitals or squeeze theorem i think
No need
just separate it
$\lim_{h\to 0}\frac{\sin h}{h}=1$
how
kheerii
what kheeri said
its an identity
or uh
something that i had memorized 
$\frac14\lim_{h\to 0}\frac{\sin\left(\frac{h}{2}\right)}{\frac{h}{2}}\cdot \frac{\sin\left(\frac{h}{2}\right)}{\frac{h}{2}}$
(q/2)(1/4) = q/8
right
y0shi

Next time just send us a picture of your question directly
wtf
Instead of trying to type it out and failing
i was struggling with this from last 1 hour, it seems like i should sleep
thanks guys
it helps
all this is assuming q isnt dependent on h. but yeah np
yea it isn't
hahaha
sleep good
u too bro
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why was my integral on the LHS wrong
ik the correct one is like arc tan something
but how do I apply that in this case? !
$\frac 1{1+4y^2} = \frac 1{1 + (2y)^2}$
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How is IP even NP-complete? I know that you can encode SAT as an IP program, proving its NP-hardness. But is there a proof that it cannot be harder than NP-complete problems? My thought is that verifying the problem should be co-NP complete. Given the optimal answer, you can plug it into the function to be minimized to get the maximum value. The answer is valid if there is no integral point inside the polytope given by the constraints + a new constraint that the optimization function to be larger than the maximum value. But, that's NP-complete because you can encode SAT in it.
@tall linden Has your question been resolved?
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@tall linden Has your question been resolved?
Maybe I'm missing something, like the information of a optimal point somehow reduces the problem into NP? I have a hunch that this is co-2QBF complete. But I have no proof.
what is IP exactly?
interactive proof?
wiki says that thats pspace, not np https://en.m.wikipedia.org/wiki/IP_(complexity)
In computational complexity theory, the class IP (interactive proof) is the class of problems solvable by an interactive proof system. It is equal to the class PSPACE. The result was established in a series of papers: the first by Lund, Karloff, Fortnow, and Nisan showed that co-NP had multiple prover interactive proofs; and the second, by Shami...
@tall linden Has your question been resolved?
Integer Programming, sorry. As in maximizing a function while having integral solution that follows the constraint.
@tall linden Has your question been resolved?
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Currently stuck at this point, I need help understanding the last step.
kisnar
which step? how to get from what you have written on paper to the answer choice?
Yes
you have x/x, that cancels. so far do you follow?
Yes
